Provided herein are methods and devices for electrohydrodynamic jet (E-jet) printing, including e-jet systems and devices of PCT Pub. No. 2009/011709 (71-07WO). In particular, the performance and throughput of E-jet systems are improved through active control of one or more parameters that affect E-jet printing by various approaches for sensing current output during printing. Utilizing the sensing and control processes provided herein provides improved e-jet printing characterized by high resolution, precision and speed, specifically improved printing registration, consistent and robust printing results (both spacing and size), droplet size control, drop-on-demand printing and single droplet deposition on the order of 1×10−6 pL. The improved printing capabilities of the present invention are applicable to a number of industries including inkjet and printed electronics, security, biotechnology (DNA and protein arrays, biosensors) and photonic industries.
Conventional sensing and monitoring techniques, such as image processing, generally require off-line data analysis and are not conducive for real-time feedback control. Accordingly, the systems and processes provided herein address the problem of providing rapid and real-time control of E-jet printing, thereby achieving significantly improved printing results as characterized by one or more of print resolution, print precision and print speed